I. Field of the Invention
The present invention relates in general to fluid filters and more particularly to a filter element having a filtering medium which is pleated or folded to give a large filtering area in a relatively small space.
II. Description of the Prior Art
It is known to form a filtering medium from a filtering material which is folded to include alternating top and bottom sections of generally triangular shape, the top sections tapering in one direction and the bottom sections tapering in the opposite direction, and side wall sections lying between the top and bottom sections and having their edges joined in the front and back at the apexes of the triangular top and bottom sections.
A filter element having a pleated filtering medium of the above described kind is disclosed in Japanese Provisional Utility Model Publication No. 62-132714 and also shown in FIGS. 13 and 14.
In the prior art filter element of FIGS. 13 and 14, the bottom sections 12 are completely coated with adhesive and bonded to a roughly flat filtering medium 13. The bottom sections 12 therefore cannot effect a filtering action.